unit Main;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls;

type
  TForm1 = class(TForm)
    Button1: TButton;
    procedure Button1Click(Sender: TObject);
  private
    { Private declarations }
    function MacAddress: string;
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}

procedure TForm1.Button1Click(Sender: TObject);
begin
  ShowMessage(MacAddress);
end;

function TForm1.MacAddress: string;
var
  Lib: Cardinal;
  Func: function(GUID: PGUID): Longint; stdcall;
  GUID1, GUID2: TGUID;
begin
  Result := '';
  Lib := LoadLibrary('rpcrt4.dll');
  if Lib <> 0 then
  begin
    if Win32Platform <> VER_PLATFORM_WIN32_NT then
      @Func := GetProcAddress(Lib, 'UuidCreate')
    else
      @Func := GetProcAddress(Lib, 'UuidCreateSequential');
    if Assigned(Func) then
    begin
      if (Func(@GUID1) = 0) and
        (Func(@GUID2) = 0) and
        (GUID1.D4[2] = GUID2.D4[2]) and
        (GUID1.D4[3] = GUID2.D4[3]) and 
        (GUID1.D4[4] = GUID2.D4[4]) and
        (GUID1.D4[5] = GUID2.D4[5]) and
        (GUID1.D4[6] = GUID2.D4[6]) and
        (GUID1.D4[7] = GUID2.D4[7]) then
      begin
        Result := 
         IntToHex(GUID1.D4[2], 2) +
         IntToHex(GUID1.D4[3], 2) +
         IntToHex(GUID1.D4[4], 2) +
         IntToHex(GUID1.D4[5], 2) +
         IntToHex(GUID1.D4[6], 2) +
         IntToHex(GUID1.D4[7], 2);
      end;
    end;
    FreeLibrary(Lib);
  end;

end;

end.
